Yose Power Triangle Battery Recall

A while back a friend of mine bought a triangle 21Ah battery from Yose Power via eBay. It stopped working and he gave it to me as it was going to cost too much to ship it back. I opened it up and was quite shocked about how badly it was put together, quite a few potentially serious flaws and the BMS had died. I put it in my "To do" pile of projects - the cells were ok and I planned to replace the BMS, rewire it etc and make it safe. Then recently he got a recall message from eBay:

If anyone has bought one of these, they might want to get in contact with Yose Power and check for recalls.

Did Yose buy them from UPP and rebadge? Perhaps they bought in bulk from the same manufacturer? Superficially, they look similar.

 

https://www.gov.uk/product-safety-alerts-reports-recalls/product-safety-report-upp-battery-e-bike-battery-packs-sold-via-amazon-alibaba-ebay-and-made-in-china-2401-0083

Did Yose buy them from UPP and rebadge? Perhaps they bought in bulk from the same manufacturer? Superficially, they look similar.

 

https://www.gov.uk/product-safety-alerts-reports-recalls/product-safety-report-upp-battery-e-bike-battery-packs-sold-via-amazon-alibaba-ebay-and-made-in-china-2401-0083

 

A similar style, but not exactly the same.

I opened it up and was quite shocked about how badly it was put together, quite a few potentially serious flaws and the BMS had died.

 

What flaws did you find?

Curious as to what flaws you found? I'll be building my own packs soon, I'm reasonably confident but it would be good to have some examples of what not to do as well.

Well, one of the worst things was that the main positive lead was made of comparatively thin wire and it ran almost in direct contact with the cells, bar a thin layer of double sided tape. The main fuse was 50A and the BMS was a high current rating too. If someone had drawn more than about 25 to 30 A, the wire would have melted through the insulation, quickly melted through the PVC insulation on the cells, and then shorted out all the banks from one end of the pack to the other.

 

I took some photos, I'll post them when I get the chance.

This is what it looks like inside:

 

 

 

See the thin red wire at the top? It runs from one end of the pack to the other right up against the cells. There is no thermal protection for the cells, like the phenolic board they used to use to house the cells on older packs. See the negative wire to the BMS, this is the sort of gauge you want for 50A, not the "bell wire" used for the positive connection.

 

Here is all the protection the cells have - a bit of tape:

 

 

 

I guess this may have caused the BMS to fail, look at the bend in the PCB from not being secured properly:

 

I can hear drawers up n down the nation rattling with the search for a screwdriver to crack open yose-power hailong style batteries for a look see and photo session. the race is on

 

ps- cracked mine a while back, looked ok iirc, both load carrying wires were of a similar substantial gauge? and no banana boards, that i would have spotted but other than that im pretty clueless..

Edited March 25, 20242 yr by thelarkbox

I can hear drawers up n down the nation rattling with the search for a screwdriver to crack open yose-power hailong style batteries for a look see and photo session. the race is on

 

I've not had a Hailong style pack, so I couldn't say. I've had several Yose Power Silverfish packs and while not perfect, they are reasonably safe. I think the problem is with these particular pack designs, especially when they are meant for high power applications.

I can hear drawers up n down the nation rattling with the search for a screwdriver to crack open yose-power hailong style batteries for a look see and photo session. the race is on

 

I've got a downtube battery a similar style to that, but not Yose... and it just so happens I've been searching in vain for photos from two years ago, which show the fish paper over one of the thicker wires degraded - adhesive melted I guess, soaked through the paper under that wire. When [mention=9614]Nealh[/mention] saw it, he said I should place some thin fibreglass board between that wire and the cells (why fish? It isn't scaly, plus it's a darkish green) to protect the cells underneath from heat - bought the board but never got around to it, but I really should, now that I've increased controller limit from 15A to 18A. I'll snap a pic later... it hasn't exploded yet. Cell group voltages were ok.

Edited March 25, 20242 yr by guerney

Apologies for keeping you in suspenders, I had other fish paper to fry. Yep, I think it's time I placed thin fibreglass board between those wires and the cells... when I can recall where I stored it - I know I placed it somewhere safe, but it's somewhere so safe I can't remember where.

 

One side:

 

 

 

Under the fish paper that side:

 

 

 

Other side:

 

 

 

Under the fish paper that side:

 

Edited March 26, 20242 yr by guerney

Very least needed is some Kapton tape between the wire insuation and nickel strip, the battery wiring placement isn't very well though out . As for having the last cell group take off in the middle of the pack , say no more !

Very least needed is some Kapton tape between the wire insuation and nickel strip, the battery wiring placement isn't very well though out . As for having the last cell group take off in the middle of the pack , say no more !

Are you talking about Gurney's battery or OP's. Gurney's one has additional fibreglass sleeving on the sense wires that cross the nickel strips, which are 100 times better than Kapton tape, and the main power wire is reinforced PTFE insulated. It exits away from the cell-pack, then turns back outside the card insulation. I don't see anything to worry about at all. Interfering with it is more likely to cause problems than leaving it alone.

Very least needed is some Kapton tape between the wire insuation and nickel strip, the battery wiring placement isn't very well though out . As for having the last cell group take off in the middle of the pack , say no more !

Are you talking about Gurney's battery or OP's. Gurney's one has additional fibreglass sleeving on the sense wires that cross the nickel strips, which are 100 times better than Kapton tape, and the main power wire is reinforced PTFE insulated. It exits away from the cell-pack, then turns back outside the card insulation. I don't see anything to worry about at all. Interfering with it is more likely to cause problems than leaving it alone.

 

Thanks battery experts! That's all good food for thought. After three years and over 4,000km with many full and partial charges, it seems likely the cells are in a good state - the last time I measured the cell banks was fresh after a full balance charge: 4.195V, 4.195V, 4.198V, 4.192V, 4.197V, 4.193V, 4.196V, 4.192V, 4.189V, 4.191V. After a previous non-balance charge, the battery pack voltage dropped off by 0.1V after about 30 minutes, was the same after 90 minutes, but I haven't measured the cell bank voltages at that point.

Edited March 26, 20242 yr by guerney

Guerney's are well protected but chaffing could possibly still occur (however unlikely) with the nickel, covering over the nickel with tape would rule out any chaffing.

https://www.newsandstar.co.uk/news/24236079.police-seize-extremely-unsafe-modified-electric-bike-carlisle/

1. Technical Description：Teflon wire is a kind of wire made of polytetrafluoroethylene (PTFE), which is widely used in various fields because of its excellent high temperature resistance, corrosion resistance and insulation properties. Heat resistant temperature. Teflon wires can withstand temperatures ranging from -180 ° C to +260 ° C；The maximum carrying capacity of the 2.5mm² Teflon line reaches 48A；And it can withstand 50A power for some time, so we are equipped with a 50A fuse. When the current reaches 50A, the fuse will disconnect the protection circuit. This is a technology fully recognized by our engineers and engineers from testing and certification agencies.
   
2. The author's title and content are sufficiently misleading. Our products have sufficient patents to prove that they are different from UPP batteries, and there is no official information that Yose Power’s batteries have been recalled.
   
3. We are a professional electric bicycle battery manufacturer since 2011, our products have undergone strict testing and passed CE certification.
   
4. Rights Statement: We appreciate and accept suggestions from everyone, but when some non-professional technical explanations appear in public channels, we also have full rights to explain and protect our brand rights.
   

1. Technical Description：Teflon wire is a kind of wire made of polytetrafluoroethylene (PTFE), which is widely used in various fields because of its excellent high temperature resistance, corrosion resistance and insulation properties. Heat resistant temperature. Teflon wires can withstand temperatures ranging from -180 ° C to +260 ° C；The maximum carrying capacity of the 2.5mm² Teflon line reaches 48A；And it can withstand 50A power for some time, so we are equipped with a 50A fuse. When the current reaches 50A, the fuse will disconnect the protection circuit. This is a technology fully recognized by our engineers and engineers from testing and certification agencies.
   
2. The author's title and content are sufficiently misleading. Our products have sufficient patents to prove that they are different from UPP batteries, and there is no official information that Yose Power’s batteries have been recalled.
   
3. We are a professional electric bicycle battery manufacturer since 2011, our products have undergone strict testing and passed CE certification.
   
4. Rights Statement: We appreciate and accept suggestions from everyone, but when some non-professional technical explanations appear in public channels, we also have full rights to explain and protect our brand rights.
   

Completely separate from your very valid point that Yosepower is not UPP...

 

Point (1) is not a completely correct description.

 

1. The principle of rating and fusing is that as we go 'downstream' each component must have a lower rating than the previous one in order to protect it. The cable 'upstream' of a 50A fuse needs a rating of not less than 50A.

2. The nominal rating of a cable is only a starting point for calculating it's safe working load in a specific situation. For example, in household wiring, when a cable passes through or is placed beneath insulation, its IEEE / BS7671 rating is greatly reduced. This is because the limiting factor is the maximum permissible temperature of the wire, which is significantly changed by the installation details.

3. A wire within a battery pack needs to be derated in the same way, to a level appropriate to the operating conditions.

4. The internal battery fuse, both its nominal value and its time-temperature behaviour, need to be conservative enough to protect that wire.

5. If regulators are happy not looking more closely, then for me it raises questions about them too.

If someone had drawn more than about 25 to 30 A, the wire would have melted through the insulation, quickly melted through the PVC insulation on the cells, and then shorted out all the banks from one end of the pack to the other.

You now know that to be false. I think you need to do something.

 

Fuses in the battery are generally not required because it's the BMS that works as a circuit breaker. If a fuse is installed, it's like a reserve measure in case the BMS fails, and would therefore have to trip after the BMS, otherwise the battery case would have to be opened to replace the fuse every time maximum current was reached. The fuse therefore needs to be rated at a higher current than the BMS.

 

Personally, I think the arrangement in the battery is pretty sound regarding the wire, BMS and fuse. The fuse gives an extra layer of safety that's not generally provided in other batteries.

 

To reach excellence, I would have liked to have seen fibreglass sleeving on the main battery wire, depending on the routing. That gives a second layer of protection, like the fuse does for the BMS. The protection would be against any fault in assembly. Without studying the assembly practices and wire routing, I couldn't say how necessary or desirable that would be.

Edited April 29, 20241 yr by saneagle

Completely separate from your very valid point that Yosepower is not UPP...

 

Point (1) is not a completely correct description.

 

1. The principle of rating and fusing is that as we go 'downstream' each component must have a lower rating than the previous one in order to protect it. The cable 'upstream' of a 50A fuse needs a rating of not less than 50A.

2. The nominal rating of a cable is only a starting point for calculating it's safe working load in a specific situation. For example, in household wiring, when a cable passes through or is placed beneath insulation, its IEEE / BS7671 rating is greatly reduced. This is because the limiting factor is the maximum permissible temperature of the wire, which is significantly changed by the installation details.

3. A wire within a battery pack needs to be derated in the same way, to a level appropriate to the operating conditions.

4. The internal battery fuse, both its nominal value and its time-temperature behaviour, need to be conservative enough to protect that wire.

5. If regulators are happy not looking more closely, then for me it raises questions about them too.

It seems we're all qualified electricians here... you're applying the rules of domestic 240v AC installation to what is, in electricians speak, a low-voltage SELV DC application. Those BS7671 rules don't apply here.

 

Even so, as you already know, fuses trip at different speeds, and these wires are not running through Rock Wool. Your argument(s) are completely irrelevant in this context.

 

YOSE - as one of the better 3rd-party battery manufacturers with a reputation worth protecting (i.e. not a fly-by-night Chinese chancer) who've sold many hundreds of faultless products to many members here on the forum - would be irresponsible to release any product that they hadn't adequately specified and tested... If they weren't confident in their product they wouldn't be here now defending it against a bunch of pseudo know-it-alls.

 

Good on YOSE for rightly defending their reputation here.

An innocent bystander’s viewpoint

 

No dog in this fight at all, but I can see Lily has won.

Local village id called her out, perhaps inadvertently or mistakenly.

Lilly took him outside and corrected him, cool.

No dog in this fight at all.

Are you sure? Maybe a badger then!

Are you sure? Maybe a badger then!

Don’t even think of the elephant in the room !

Sorry to have ruffled feathers, not my intention, I just like to understand things from first principles. If my concern is unfounded, happy to have that explained.

 

The answers I would want to find are (1) at continuous 50A i.e just not quite blowing the fuse, how hot does the 2.5mm2 cable get, in its installed position within the battery; (2) is that temperature level a concern given its proximity to the lithium ion cells?

 

I do understand that the majority of ebikes, and all 250W rated legal pedelec motors are never going to draw anything like 50A, and so will not have a problem. But big 21Ah, 50A capable batteries will get used by some people to their maximum capabilities, and that is where the problem lies.

 

I would be either reducing the fuse rating or increasing the cable size to achieve a cable significantly more capable than the fuse rating, adding to safety at very low cost.

I would be either reducing the fuse rating or increasing the cable size to achieve a cable significantly more capable than the fuse rating,

That's conventional electricians logic...

 

A standard UK ring main today is wired with 16A 2.5mm copper PVC insulated, fused at 32A.

In the 1960's/70's there was a period where the UK wired that same circuit with 1.5mm copper MINERAL insulation and still fused at 32A. In other words, a 1.5mm gauge is rated the same as 2.5mm to carry the same current and that's only down to the change in insulation (yes, that is in BS7671!).

 

I don't know how Teflon/PTFE insulation behaves/allows higher current other than YOSE's comments here as a result of their own design testing, but the point is is that you can't make assumptions on current carrying capability based purely on wire gauge; the insulation has a big part to play.

 

A 13A BS1363 British plug fuse typically doesn't blow until 26A. A fast blow equivalent blows in milliseconds at the rated current.

 

I'm no expert, but YOSE's logic does seem to make sense even if it defies the usual "thick wire, smaller fuse" thinking.